Many granular comestible products, such as instant beverage mixes, are sold in jars which are closed by threaded caps. The quality of the granular comestible product deteriorates rapidly upon exposure to air, due in part to the large surface area of the granular composition. Thus, many instant beverage products are packed using an inner seal to exclude any contact with ambient air during shipping and marketing.
However, the inner seal must be removed to make use of the product; thereafter, the jar cap must be relied upon to preserve the freshness and flavor of the product. Ironically, the cap must be removed from the jar each time it is desired to use the product. Unscrewing and resecuring the jar top is a minor inconvenience to the user of the product, but repeated opening of the jar exposes the contents to large amounts of oxygen laden ambient air. For example, a large jar of instant coffee may be opened and resealed as many as two hundred times before the contents of the jar are completely used. Renewing the oxygen supply of the air within the jar two hundred times causes a serious deterioration in the flavor, aroma, and freshness of the product.